On a plane
Downslope
dispersion
Directional
bias
Channelized
vs unchannelized flow
•We use D-∞ for unchanneled areas, because it allows downslope dispersion.
•Once flow is channelized, we want to preclude dispersions, so use D-8.
•To address directional bias, we direct flow to the downslope cell with greatest plan curvature, rather than steepest descent. Traced channels then follow contour crenulations.
Flow Direction